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Book digitized by Google from the library of Harvard University and uploaded to the Internet Archive by user tpb. Topics: Cone, Conics, Spherical Source: http://books.google.com/books?id=nGwLAAAAYAAJ&oe=UTF-8

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Book digitized by Google from the library of University of California and uploaded to the Internet Archive by user tpb. Topics: Cone, Conics, Spherical Source: http://books.google.com/books?id=pRNDAAAAIAAJ&oe=UTF-8

eye237

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Aircraft with supersonic, short takeoff, and vertical landing capability were proposed to replace some of the current high-performance aircraft. Several of these configurations use a ventral nozzle in the lower fuselage, aft of the center of gravity, for lift or pitch control. Internal vanes canted at 20 deg were added to a swivel-type ventral nozzle and tested at tailpipe-to-ambient pressure ratios up to 5.0 on the Powered Lift Facility at NASA LeRC. The addition of sets of four and seven... Topics: ERROR ANALYSIS, GEOSYNCHRONOUS ORBITS, LAUNCH WINDOWS, LUNAR ORBITS, SPACECRAFT LAUNCHING, TRANSFER...

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The design of a fly-by-wire control system having a mission failure probability of less than one millionth failures per flight hour is examined. Emphasis was placed on developing actuator configurations that would improve the system performance, and consideration of the practical aspects of sensor/computer and computer/actuator interface implementation. Five basic configurations were defined as appropriate candidates for the F-8C research aircraft. Options on the basic configurations were... Topics: BODIES, LEAST SQUARES METHOD, COMPUTER GRAPHICS, CURVE FITTING, SURFACE GEOMETRY, CONICS,...

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Often in spaceflight proposal development, mission designers must eva luate numerous trajectories as different design factors are investiga ted. Although there are numerous commercial software packages availab le to help develop and analyze trajectories, most take a significant amount of time to develop the trajectory itself, which isn't effectiv e when working on proposals. Thus a new code, PatCon, which is both q uick and easy to use, was developed to aid mission designers to condu ct trade... Topics: NASA Technical Reports Server (NTRS), TRAJECTORIES, COMPUTER PROGRAMS, LAUNCHING, SPACE FLIGHT,...

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A method is presented for calculating trajectories for the restricted problem of three bodies which utilizes conic propagation of the state vector with frequency correction of position and velocity by means of a constant or slowly varying function. This method of calculating trajectories was applied to the planar circular restricted three body problem, the planar elliptic restricted problem, and the ephemeral restricted problem. Two methods (the refined method and the straight forward method)... Topics: NASA Technical Reports Server (NTRS), THREE BODY PROBLEM, TRAJECTORY ANALYSIS, CONICS, EARTH...

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A class of optical surfaces called 'Swept Conics' or 'Conical Spheroids' can be used to transform wavefronts from point sources to diffraction limited line or arc images, and vice versa. Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, MIRRORS, CONICS, ROTATION, SYMMETRY,...

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The Hubble Space Telescope backup secondary mirror was tested to determine the vertex radius and conic constant. Three completely independent tests (to the same procedure) were performed. Similar measurements in the three tests were highly consistent. The values obtained for the vertex radius and conic constant were the nominal design values within the error bars associated with the tests. Visual examination of the interferometric data did not show any measurable zonal figure error in the... Topics: NASA Technical Reports Server (NTRS), ERROR ANALYSIS, HUBBLE SPACE TELESCOPE, MIRRORS, PERFORMANCE...

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This report consists of a copy of a paper that has been submitted to the 'Journal of Geophysical Research', entitled 'DE 1 and Viking Observations Associated With Electron Conical Distributions,' and an abstract of another paper (included as an appendix to the report) that is about to be submitted to the same journal entitled 'Perpendicular Electron Heating by Absorption of Auroral Kilometric Radiation.' A bibliography of other papers that have been published as a result of this project... Topics: NASA Technical Reports Server (NTRS), AURORAS, ELECTRON DISTRIBUTION, PLASMA HEATING, RADIATION...

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Ground-based model scale aeroacoustic data is frequently used to predict the results of flight tests while saving time and money. The value of a model scale test is therefore dependent on how well the data can be transformed to the full scale conditions. In the spring of 2000, a model scale test was conducted to prove the value of chevron nozzles as a noise reduction device for turbojet applications. The chevron nozzle reduced noise by 2 EPNdB at an engine pressure ratio of 2.3 compared to that... Topics: NASA Technical Reports Server (NTRS), AEROACOUSTICS, NOISE REDUCTION, AIRCRAFT NOISE, AERODYNAMIC...

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A computer program calculates a best conic fit of a given spacecraft trajectory. Spacecraft trajectories are often propagated as conics onboard. The conic-section parameters as a result of the best-conic-fit are uplinked to computers aboard the spacecraft for use in updating predictions of the spacecraft trajectory for operational purposes. In the initial application for which this program was written, there is a requirement to fit a single conic section (necessitated by onboard memory... Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, CONICS, SPACECRAFT TRAJECTORIES,...

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This paper is a presentation of some practical aspects of orbital transfer from Geosynchronous Transfer Orbit (GTO) to close, near-circular orbits of the Moon. The intent is to identify the important parameters affecting the problem and to bound (approximately) the range of required delta V for a spacecraft that has been placed in GTO. The basic geometric relationships are described and the dynamics are simulated by use of the Zero-Sphere-of Influence Patched Conic method. It is found that the... Topics: NASA Technical Reports Server (NTRS), ERROR ANALYSIS, GEOSYNCHRONOUS ORBITS, LAUNCH WINDOWS, LUNAR...

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The fundamental geometrical characteristics of spiral bevel gear tooth surfaces are discussed. The parametric representation of an ideal spiral bevel tooth is developed based on the elements of involute geometry, differential geometry, and fundamental gearing kinematics. A foundation is provided for the study of nonideal gears and the effects of deviations from ideal geometry on the contact stresses, lubrication, wear, fatigue life, and gearing kinematics. Topics: NASA Technical Reports Server (NTRS), GEAR TEETH, GEARS, MECHANICAL DRIVES, CONICS, CURVES...

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One geometry currently under consideration for the Aeroassist Flight Experiment (AFE) vehicle is composed of several segments of simple general conics: an ellipsoidal nose tangent to an elliptical cone and a base skirt with the base plane raked relative to the body axis. An analytic representation for the body coordinates and first and second partial derivatives of this configuration has been developed. Equations are given which define the body radius and partial derivatives for a prescribed... Topics: NASA Technical Reports Server (NTRS), AEROASSIST, CONICS, GEOMETRY, RESEARCH AIRCRAFT, AIRCRAFT...

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Landforms in arid regions record the interplay between tectonic forces and climate. Alluvial fans are a common landform in desert regions where the rate of uplift is greater than weathering or sedimentation. Changes in uplift rate or climatic conditions can lead to isolation of the currently forming fan surface through entrenchment and construction of another fan either further from the mountain front (decreased uplift or increased runoff) or closer to the mountain front (increased uplift or... Topics: NASA Technical Reports Server (NTRS), ALLUVIUM, DIGITAL DATA, ELEVATION, FANS (LANDFORMS), RADAR...

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The geometry of general three-dimensional bodies was generated from coordinates of points in several cross sections. Since these points may not be on smooth curves, they are divided into groups forming segments and general conic sections are curve fit in a least-squares sense to each segment of a cross section. The conic sections are then blended in the longitudinal direction through longitudinal curves. Both the cross-sectional and longitudinal curves may be modified by specifying particular... Topics: NASA Technical Reports Server (NTRS), BODIES, COMPUTER GRAPHICS, CURVE FITTING, SURFACE GEOMETRY,...